A backplane physically includes a set of electrical connectors to interconnect data, control, and power between a set of modules, line cards, circuit cards, blades, etc. (collectively referred to as “modules”). In networking and computing applications, devices such as network elements, switches, routers, servers, storage devices, etc. (collectively referred to as “network elements”) can utilize a modular physical implementation where functionality is implemented on various modules which plug into the backplane. Of note, network elements continue to grow in terms of the amount of data supported in single configurations. Conventionally, a typical network element physically supports hundreds of Gb/s of data connectivity. However, network elements are evolving to support Tb/s of data connectivity and beyond in a single rack or frame or even in a single shelf or chassis. In conventional implementations, backplanes are used to interconnect all data, control, and power to all pluggable modules. For power, there are typically two feeds, A and B, to each module. The power feeds are typically copper distribution layers on the backplane. With the two power feeds, A and B, distributing both supply and return currents, four or more heavy copper layers are required on the backplane.
Conventionally, one large backplane includes signal layers intermixed with power layers. The total number of layers would be X signal layers plus Y power layers. Adding all these layers up increases the price of the backplane and increases the aspect ratio (hole size to board thickness). Small holes are harder to do as thickness increases, so it is desirable to reduce the Printed Circuit Board (PCB) thickness. The area of the backplane may also be up to twice as big and limit the locations where the backplane can be manufactured due to equipment capabilities. Conventional approaches result in a single backplane PCB that is about twice the cost of the combined separate signal and power backplanes. The conventional approach also can cause signal integrity problems when connector holes get very thick/long affecting the signal quality. Another approach is to split the backplane closer to power inputs but not spanning the whole module. This option still requires many power layers on the backplane resulting in a thicker and larger backplane.